The fiery prison riot scene was over and, mopping the sweat from his brow, actor Jackie Earle Haley was heading back to his trailer in seach of some lunch. It was a crisp fall day in 2007 on the set of " Watchmen," the most challenging comic-book movie project ever filmed, and Haley was trying to soak in every heroic moment. "I'm just happy to be here, to be part of something like this," said Haley, a child star in the 1970s ("The Bad News Bears," "Breaking Away") who saw his film dreams fade as he ended up driving a limo, delivering pizzas and doing other odd jobs.

After more than a decade off the Hollywood grid, Haley surged back on the scene with his Oscar-nominated performance as a sex offender in the 2006 film "Little Children," and with "Watchmen," may have the opportunity to deliver another memorable character. "This is one of those roles that stays with you a long time, for the actor and the audience," Haley said of Rorschach, the grim vigilante at the center of the epic movie, which brings to life the landmark 1986 graphic novel by Alan Moore and Dave Gibbons. The actor added muscle and went into dark areas to essay a hero who is more like "Taxi Driver's" Travis Bickle than Batmobile owner Bruce Wayne.

"The one thing that's super difficult about this part is to find that place of release," Haley said. "Actors continually need to push away all inhibitions, and you need to reconcile your mind with where the character is. You need to find the moment and communicate." And then there's the really hard part: "I have to do all of that with a sock over my head."

That costume challenge is part and parcel of the modern superhero cinema; the sector's ambitions are far higher today than in years past, as "The Dark Knight" and "X-Men" proved, but there's still that nettlesome matter of those capes. Moviegoers of a certain age still think of Adam West when they see a masked man. No superhero film is trying to push further away from that camp than "Watchmen," an R-rated epic that tells a multi-generational fable about a violent fringe tribe not unlike, say, "GoodFellas." For the uninitiated, "Watchmen" is a revered masterpiece for comics fans and has frequently been described as "unfilmable," a word even director Zack Snyder ("300") has used with a smirk while talking about his film, scheduled to hit theaters in March.

Not only is the source material challenging (there's the scope of the story and its especially lurid take on heroes), but the property followed a notoriously difficult path to the screen. The story begins in the 1980s. Snyder's challenge has been not only to present an alternative America that has a rich and complicated history involving two generations of masked-and-caped crime fighters (though there's only one truly super-powered being, Dr. Manhattan) but also one where Richard Nixon is in his fifth term in the White House.

And even now, the release date of the Warner Bros. film may be subject to change because of a legal challenge by rival studio Fox, which once held rights.

Also, Moore, viewed as an iconoclastic genius in comics, has taken his name off the project because of his entrenched antipathy for Hollywood and all of its pursuits. "I will be spitting venom all over it," Moore told The Times in September, adding that he views the tale as "inherently unfilmable." There's that word again.

Despite the turbulence, there has been massive fan interest. At the heart of "Watchmen" is a murder mystery: Who killed the thuggish hero who called himself the Comedian? Rorschach -- who mutters, wears a strange, blotchy mask and is viewed as a nut job even by his costumed peers -- is the tenacious follower of clues that lead to a plot that could kill millions. Snyder said he purposely went for actors whose faces are not locked into the public imagination.

"I think if you have a Tom Cruise, someone of that stature of fame, it makes it harder to present this other world and keep the viewer right there in it," the director said.

Snyder said no character is more important than Rorschach, whose name hints at the psychological undercurrents that made the graphic novel so gripping. The filmmaker said he "is easily one of the greatest comic book characters ever," and that's a view shared by many fans and the press that serves them. Last year, Wizard Magazine, the most popular publication for American comics fans, ranked Rorschach as the sixth-greatest comic-book character ever, right between the Joker and Captain America.

Haley, meanwhile, is poised for a big year with a role in Martin Scorsese's "Shutter Island." "I can't tell you how much you appreciate things when you come back through a second time, when you get that kind of chance," Haley said.

Even when you have to wear a sock on your head?

"You know, actually, there was something very empowering about the costume, about that mask and the way you feel when you wear it," Haley said. "At one point, we were filming a cemetery scene and I looked down and I saw my shadow -- the coat, the hat, the mask -- and I had this powerful jolt. 'That's Rorschach.' The costume is the challenge, but the costume is also the power."